Definition
Total Parenteral Nutrition (TPN) is a life-sustaining medical therapy that delivers complete nutrition intravenously, bypassing the gastrointestinal tract entirely. It’s used when a patient’s digestive system is nonfunctional, inaccessible, or needs complete rest—such as in cases of short bowel syndrome, bowel obstruction, severe Crohn’s disease, or after major abdominal surgery
Intravenous administration of varying combinations of hypertonic or isotonic glucose, lipids, amino acid, electrolytes, vitamins and trace elements through a venous access device (VAD) directly into the intravascular fluid to provide nutrients for patients who are unable to receive adequate nutrition through GI tract.
Purposes
- To provide nutrients required for the normal metabolism, tissue maintenance, repair, and energy demands.
- To bypass the GI tract for patients who are unable to take food orally.
Indications
- Patients who cannot tolerate enteral nutrition because of:
- Paralytic ileus.
- Intestinal obstruction.
- Acute pancreatitis.
- Short bowel syndrome.
- Inflammatory bowel disease.
- Gastrointestinal fistula.
- Severe diarrhea, e.g., ulcerative colitis.
- Persistent vomiting.
- Malabsorption.
- Hypermetabolic states for which enteral therapy is either not possible or inadequate:
- Severe burns.
- Trauma/surgery when nothing can be taken by mouth for more than 5 days.
- Acute renal failure.
- Multiple fractures.
- Tumor in GI tract.
- Patient at risk for malnutrition because of:
- Gross underweight (more than 80% below the standard).
- Metastatic cancer.
- “Nil per oral”(NPO) for more than 5 days.
Contraindications
1. Functional and accessible gastrointestinal tract.
2. Patient is able to tolerate oral feed.
Methods of Parenteral Nutrition
1. Total nutrient admixture (TNA) into a central vein:
- This parenteral formula combines carbohydrates in the form of a concentrated (20-70%) dextrose solution, protein in the form of amino acids; lipids in the form of an emulsion (10-20%), including triglycerides, phospholipids, glycerol and water; vitamins, and minerals.
- It is indicated for patients requiring parenteral feeding for seven or more days. Given through a central vein. Often into the superior vena cava.
2. Peripheral parenteral nutrition (PPN):
- This parenteral formula combines carbohydrates as a lesser concentrated glucose solution with amino acids, vitamins, minerals, and lipids.
- Given through a peripheral vein and it is indicated for patients requiring parenteral nutrition for fewer than 7 days.
3. Total parenteral nutrition (TPN):
- This parenteral formula combines glucose, amino acids, vitamins, and minerals.
- Given through a central IV line. If lipids are needed, they are given intermittently mixed with the TPN.
4. Fat emulsion (lipids):
- It is composed of triglycerides (10-20%), e.g., phospholipids, glycerol, and water.
- May be given centrally or peripherally.
Articles
- Central VADs: Long-term VADS such as Hickman, Broviac or Groshong catheters or peripherally inserted central catheter (PICC line) or peripheral IV acces
- Volume control infuser.
- Filters:
- 0.22 micron for TPN (without fat emulsion).
- 3.2-micron filter for TNA or fat emulsion.
- Bag of parenteral nutrition.
- Administration tubing with Luer-lock connections.
- Hypoallergic tape.
- Face mask (optional).
- Sterile gloves.
Procedure
| Nursing Actions | Rationale | |
| 1. | Before procedure Assess the need for parenteral nutrition by performing nutritional assessment. | Provides baseline data to compare changes after parenteral nutrition is started. |
| 2. | Check physician’s order for method of parenteral nutrition (TNA, TPN, PPN or lipids) and flow rate. | Parenteral therapy must be ordered by physician. |
| 3. | Explain the procedure in detail to the patient and relatives. | |
| 4. | Obtain informed consent. | |
| 5. | Collect needed equipment for the procedure. | |
| 6. | Remove the bag of parenteral nutrition from refrigerator at least 1 hour before procedure (if refrigerated). | Decreases incidence of hypothermia, pain, and vasospasm. |
| 7. | Inspect fluid for presence of creaming or any change in constitution. | Indicates fluid separation. TPN solution should be clear without clouding. |
| 8. | During procedure Wash hands, don cap, mask, gown, and sterile gloves. | Follows very strict aseptic precautions. |
| 9. | Using strict aseptic technique, attach tubing (with filter) to TNA bag and purge out air. | Prevents chances of developing air embolus. |
| 10. | Close all clamps on new tubing and insert tubing into volume control infuser. | |
| 11. | Place the patient in supine position and turn head away from VAD insertion site. | Supine position with head turned to one side opens the angle between clavicle and first rib. |
| 12. | Clean the insertion site with alcohol and povidone-iodine solution. | |
| 13. | Assist physician while inserting VAD. | |
| 14. | After procedure Insertion of VAD, connect tubing to hub of VAD using sterile technique and make sure that the connection is secured using Luer-lock connection. | |
| 15. | Open all clamps and regulate flow through volume control infuser. | |
| 16. | Monitor administration hourly, assessing for integrity of fluid and administration system, and patient tolerance. | |
| 17. | Record the procedure. |
(TNA: total nutrient admixture: TPN: total parenteral nutrition: PPN: peripheral parenteral nutrition; VAD: venous access device)
Complications
| COMPLICATIONS OF TPN | |||
| Complications | Causes | Interventions | |
| 1. | Sepsis | High glucose content of fluid. VAD contamination. | Monitor temperature, WBC count, and insertion site for signs and symptoms of infection. Maintain strict surgical asepsis when changing dressing and tubing. Consider decreasing glucose content of fluid. Consider removal of VAD with replacement in alternate site If blood culture is positive, consider institution of antibiotic therapy. |
| 2. | Electrolyte imbalance | Iatrogenic. Effect of underlying diseases, i.e. fistula, diarrhea, vomiting. | Monitor for signs and symptoms of electrolyte imbalances. Treat underlying cause.Change concentration of electrolytes in TNA as necessary. |
| 3. | Hyperglycemia | High glucose content of fluid. Insufficient insulin secretion. | Monitor blood glucose frequently.Decrease glucose content of fluid, if possibleAdminister exogenous insulin. |
| 4. | Hypoglycemia | Abrupt discontinuation of TNA administration through a central vein. | After discontinuation of centrally administered TNA, start 10% dextrose at the same rate. |
| 5. | Hypervolemia | Iatrogenic. Underlying disease such as congestive heart failure and renal failure. | Monitor intake and output, daily weight, CVP, breath sounds, and peripheral edema. Consider administering more concentrated TNA solution. |
| 6. | Hyperosmolar diuresis | High osmolarity of parenteral nutritional fluid. | Consider decreasing the concentration or amount of fluid administered. |
| 7. | Hepatic dysfunction | High concentration of carbohydrates/fats relative to protein. | Monitor liver function tests, triglyceride levels, and presence of jaundice.Consider alteration in formula. |
| 8. | Hypercarbia | High carbohydrate content of fluid. | Consider changing formula to increase the proportion of fat relative to carbohydrate. |
| 9. | Lipids intolerance | Low birth weight or premature infant. History of liver disease. History of elevated triglycerides. | Monitor for bleeding. Monitor oxygen levels for impaired oxygenation. Monitor fat overload syndrome. Monitor triglyceride levels and liver function test, hepatosplenomegaly, decreased coagulation, cyanosis, dyspnea. Monitor allergic reactions such as nausea, vomiting, headache, chest pain, back pain, and fever. Administer lipid-containing solution slowly. |
| 10 | Lipid particulate aggregation | Unstable mixture of dextrose solution with lipid emulsion. | Observe for cracking or creaming of fluid and avoid use of fluid with these characteristics. |
Special Considerations
- Strict surgical asepsis is mandatory throughout the insertion of the catheter when handling the solution and tubes and when caring for the site of insertion. The parenteral line can serve as an excellent culture medium since it directly leads to blood, and bacterial invasion leads to septicemia.
- Psychological support is necessary as the patient is not taking anything orally for a long time.
- As nothing enters the GI tract, bowel elimination will decrease, and it should be explained to the patient.
- Because TPN solutions are high in glucose, infusions are started slowly to prevent hyperglycemia.
- Rate of infusion for an adult is 1 liter (40 mL/h) the first day, 2 liters (80 mL/h) for 24 to 48 hours, and 3 liters (120 mL/h) within 3 to 5 days.
- To prevent hypoglycemia, while discontinuing parenteral nutrition, the solution should be reduced gradually over 48 hours.
- Total parenteral nutrition is given for fewer than 7 days.
- Monitor laboratory investigations before administering TPN.
- Monitor strict intake and output.
- Check temperature of the TPN solution. Ensure it is not cold.
- Do not discontinue TPN abruptly.
Port for TPN infections should not be used to obtain blood samples, CVP reading and administering of other fluid/medications
REFERENCES
- Annamma Jacob, Rekha, Jhadav Sonali Tarachand: Clinical Nursing Procedures: The Art of Nursing Practice, 5th Edition, March 2023, Jaypee Publishers, ISBN-13: 978-9356961845 ISBN-10: 9356961840
- Omayalachi CON, Manual of Nursing Procedures and Practice, Vol 1, 3 Edition 2023, Published by Wolters Kluwer’s, ISBN: 978-9393553294
- Sandra Nettina, Lippincott Manual of Nursing Practice, 11th Edition, January 2019, Published by Wolters Kluwers, ISBN-13:978-9388313285
- Adrianne Dill Linton, Medical-Surgical Nursing, 8th Edition, 2023, Elsevier Publications, ISBN: 978-0323826716
- Donna Ignatavicius, Medical-Surgical Nursing: Concepts for Clinical Judgment and Collaborative Care, 11th Edition ,2024, Elsevier Publications, ISBN: 978-0323878265
- Lewis’s Medical-Surgical Nursing, 12th Edition,2024, Elsevier Publications, ISBN: 978-0323789615
- AACN Essentials of Critical Care Nursing, 5th Ed. Sarah. Delgado, 2023, Published by American Association of Critical-Care Nurses ISBN: 978-1264269884
- Ernstmeyer K, Christman E, editors. Nursing Fundamentals [Internet]. 2nd edition. Eau Claire (WI): Chippewa Valley Technical College; 2024. PART IV, NURSING PROCESS. Available from: https://www.ncbi.nlm.nih.gov/books/NBK610818/
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